GNETOPHYTES & ALVAREZSAURS

[darren.naish@port.ac.uk]

On gnetophytes etc, Nick L asked...

> Do either of these guys have any fossil record at all?

Yes, gnetophyte pollen is known from the Triassic and the Cretaceous 
and is apparently near-indistinguishable from that of _Ephedra_. Work 
on gnetophyte phylogeny indicates that _Welwitschia_ diverged during 
the Cretaceous I believe (the ucmp website had a good section on 
gnetophyte fossils but wasn't working last time I checked). If the 
Triassic record is valid then, as some have argued, it might be that 
angiosperms originated in the Triassic.

Fond as I am of Nick's suggestion that alvarezsaurids might have been 
ant-eaters.. Nick, have you looked at a tarsipedid (honey possum) 
skull? Obviously lacks the postcranial specialisations seen in 
alvarezsaurids and extant myrmecophagous forms but the skull 
morphology is superficially similar.

DARREN NAISH 
PALAEOBIOLOGY RESEARCH GROUP
School of Earth & Environmental Sciences
UNIVERSITY OF PORTSMOUTH
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